Miss Otis regrets - Cole Porter - Night and Day movie

The well-known song, "Miss Otis regrets", composed by Cole Porter, and first published in 1934, and as featured in the 1946 movie "Night and Day", a biography of the said composer.
*****Update:- I have been reliably informed that the singer in this clip is Monty Woolley playing as himself, with Cary Grant (playing the piano) playing the character of Cole Porter.